This proposal seeks continued support for research projects in the Computer Medicine Laboratory, Department of Medicine, Harvard Medical School at the Beth Israel Hospital. This research was begun when projects previously directed independently by Dr. Howard Bleich, at the Beth Israel Hospital, and Dr. Warner Slack, at the University of Wisconsin, were united, and when the increased productivity that would result from close collaboration became apparent. The goal of this research is to test the hypothesis that computer programs can favorably influence the cost, quality, and availability of medical care. Support is requested for research within four distinct but interrelated areas: 1) Interactive consulation programs for physicians; implementation and evaluation; 2) Interactive storage and retrieval programs; evaluation of therapeutic regimens; 3) Interactive consultation programs for patients; implementation and evaluation; 4) Hospital information systems; cost benefit analysis. Our short-term goal is to demonstrate, if we can, that patients benefit from the use of each of our programs. Our long-range goal is to utilize the data base generated by each of the projects for the benefit of the others; in this way, programs that are medically beneficial can be deployed, both in our hospital and in places of export, under conditions that are economically convincing.